1. Technical Field
Example embodiments relate to semiconductor memory devices, for example, to nonvolatile memory devices, methods of operating nonvolatile memory devices and memory systems including nonvolatile memory devices.
2. Description of Related Art
A semiconductor memory device is a memory device that can store data and readout the stored data when necessary. A semiconductor memory device is classified into a volatile memory device and a nonvolatile memory device.
A volatile memory device loses stored data when its power supply is interrupted. Examples of volatile memory devices include SRAM, DRAM and SDRAM. A nonvolatile memory device maintains stored data even when its power supply is interrupted. Examples of nonvolatile memory device include ROM, PROM, EPROM, EEPROM, a flash memory device, PRAM, MRAM and FRAM. A flash memory device is classified into a NOR-type flash memory and a NAND-type flash memory.